Manufacture of sulphur dyestuffs



Patented Dec. 7, 1926.

{UNITE STATES 1,609,927 PATENT OFFICE.

'-"JOHANNES WUTKE, OF WOLFEN KREIS' BITTER-FELT), AND WALTER HAGGE, OF DES- SAU IN .ANHALT, GERMANY, ASSIGNORS TO I. G. FARBENINDUSTRIE AKTIENGE- SELLSCHAFT, F FRANKFURT, GERMANY. I

MANUFACTURE OF SULPHUR DYESTUFF S.

No Drawing. Application filed June 8, 1925, Serial No. 35,744, and in Germany June 14, 1924.

It is known that in the manufacture of vention without limiting it, the parts being sulphur dyestuffs an addition of copper to the reaction mixture varies the tone of the color produced. This was first described in the German specification 101,577 which describes the production of a green sulphur dyestufi by the fusion of i-nitroor 4-aminol-hydroxybenzene with sodium hydroxide, sulphur and a copper salt. German specification 162,156 relates to the manufacture of a clear yellow reen sulphur dyestufi' from the indo henol (L erived from l-phenylaminonaphtha ene-S-sulphonic acid and -aminol-l'iydroxybenzene by fusion with a polysulphide with addition of copper, while without copper there is produced a less vivid green blue dyestutf. 1n the manufacture of violet to brown-red sulphur dyestuffs from azines an addition of copper makes the color tone clearer and more red. (Compare for example the German specifications 171,177 and 179,960).

In.all these cases an addition of copper determines the diminution of the black and blue contents of the dyeing, .so that the tint is more vivid and therefore of more value.

The copper has hitherto been added to the reaction mixture in Various forms, as metallic copper (generally copper bronze) as a soluble salt (generally copper sulphate), as oxide or as sulphide. Since however both metallic copper and copper oxides and the usual copper salts become copper sulphide in the sulphur melt, in all cases the process amounts to a sulphurization in the presence of copper sulphide.

According to the present invention in the manufacture of sulphur dyestuffs with addition of copper the color tone produced is still clearer if the formation of copper sulphide is avoided.

It is possible to avoid the formation of copper sulphide if, for example, there is used in the melt, copper in the form of a complex salt, such as an alkali metal cupro-cyanide, for instance potassium cupro-cyanide K [Cu (CN) which does not form copper sulphide by reaction with alkali sulphide. Such a melt may be obtained by adding to the melt containing copper in any form, an alkali cyanide so as to convert the copper sulphide produced into complex compounds.

The following examples illustrate the inby weight:

1. 25 parts of sulphur are dissolved in 85 parts of crystallized sodiumsulphide and there are added at the boiling point 42.6 parts of the leuco-indophenol from l-phenylaminonaphthalene-S-sulphonic acid and 4- amino-l-hydroxybenzene, having most probably the formula:

HO; NO 11 together with a solution of potassium cuprocyanide prepared from 7 parts of copper sulphate crystals and the corresponding proportion of potassium cyanide. The mixture is heated in the reflux apparatus at 110 to 115 C, until the formation of the dyestutf is at an end, whereupon the dyestufl' is worked up in the usual manner. It dyes cotton pure yellow green.

. 2. Into a polysulphide solution made from 110 parts of crystallized sodium sulphide and 50 parts of sulphur are introduced 20 parts of 3-amino-dhydroxydiphenazine having most probably the formula:

and a solution of potassium cupro-cyanide made from 8 parts of copper sulphate crystals. The whole is boiled at 110C. for about 30 hours until the formation of the dyestufl' is at an end. The dyestuff yields clear yellow-red dyeings.

What we claim is,

1. The herein-described manufacture of sulphur dyestuffs by conducting the sulphurization in presence of a copper compound, which is not transformabl'e into copper sulphide under the conditions of the reaction.

2. The herein-described manufacture of sulphur dyestuffs by conducting the sulphurization in the presence of a complex copper cal with sulphur dyestuffs obtainable by the herein-described process which consists essentially in conducting the sulphurization in the presence of a copper compound which is der the conditions of the reaction; said dyestuffs possessing clearer and redder color tones than dyestuffs produced by sulphurization in the presence of copper compounds transformable into copper sulphide under the conditions of the reaction.

In testimony whereof We afiix our signatures.

J OHANNES 'WUTKE. WALTER HAGGE.

not transformable into copper sulphide un- 

